Isocyanate - reactive benzoate adduct polyol for use in the prodcution of rigid foam

ABSTRACT

A polyol solution containing one or a combination of a benzoate glycol adduct, a substituted benzoate glycol adduct, a napthenate glycol adduct, a substituted naphthenate glycol adduct, a toluate glycol adduct, or a substituted toluate glycol adduct, and a closed cell, rigid polymer foam formed as a reaction product of the polyol solution, which foam comprises the reaction product of a polyisocyanate and an isocyanate-reactive component in the presence of a catalyst and a hydrogen-containing blowing agent or mixture of hydrogen-containing blowing agents, wherein the isocyanate-reactive component comprises a mixture of a hydroxy terminated polyester and a polyester comprised of the benzoic acid glycol adduct, toluic acid glycol adduct, or napthoic acid glycol adduct Foams prepared from the mixture have superior thermal conductivity, lower flammability, and higher stability of the emulsified liquid reactants prior to polymerization.

FIELD OF THE INVENTION

[0001] The invention relates to an isocyanate-reactive composition for use in the preparation of rigid polyisocyanurate and polyurethane foams. More particularly, the invention relates to an isocyanate-reactive composition which is readily miscible with hydrocarbon blowing agents.

BACKGROUND OF THE INVENTION

[0002] Rigid polyurethane foams may be prepared by the reaction of a polyisocyanate, an isocyanate-reactive polyol, and a blowing agent in the presence of a catalyst. Polyisocyanurate foams, a variety of polyurethane in which some of the isocyanate components of the reaction mixture are catalyzed to react with themselves creating strong isocyanurate linkages, can be formed with the polyurethane foams. A variety of polyols may be used for foam preparation, with the particular polyol chosen based on the desired results of the foam or compatibility with other reactants. Polyurethane and polyisocyanurate foams produced by traditional methods have employed chlorofluorocarbons such as trichlorofluoromethane (CFC-11) as the blowing agent. These chlorofluorocarbon compounds are volatized during the exothermic reaction of isocyanate with the polyester polyol. The expanding gas is entrapped within the foam reaction mixture, which polymerizes to form an insulating cellular structure.

[0003] Recent studies have shown that the halogen components of chlorofluorocarbon foam blowing agents, such as CFC-11, deplete ozone in the stratosphere. Hydrochlorofluorocarbons (HCFCs), such as dichlorofluoroethane (141b) and chlorodifluoromethane (HCFC-22), are partially halo-substituted hydrocarbons that have lower ozone depletion potential than the fully halogenated chloroflourocarbons (CFCs) and have, accordingly, been used as alternative blowing agents for CFC-11 in foam production. But, ever increasing environmental regulation has placed severe burdens and costs upon the users of HCFCs as well as CFCs.

[0004] With the heavy regulation of CFCs and HCFCs there has been renewed interest in the use of simple hydrocarbons as blowing agents. Hydrocarbons, such as the isomeric forms of pentane, do not contain halogen components, and are therefore not expected to deplete stratospheric ozone. Hydrocarbon blowing agents have not been favored in the past because of their higher flammability and because of the higher thermal conductivity of the foam produced with the hydrocarbon blowing agents.

[0005] More importantly, from a production viewpoint, hydrocarbon blowing agents have limited miscibility with polyester polyols, particularly in the aromatic polyester polyols preferred for making polyurethane and polyisocyanurate insulating foams. Additionally, the low solubility of hydrocarbon blowing agents in polyols, particularly in aromatic polyester polyols, requires that the producer modify his conventional foaming equipment to process these materials.

DESCRIPTION OF THE PRIOR ART

[0006] The prior art discloses a variety of methods for compatibilizing blowing agents within a polyol mixture. For instance, U.S. Pat. No. 4,444,920 to Brennan discloses the catalyzed reaction and subsequent transesterification of alkyl p-formylbenzoate from a DMT production process in order to compatibilize the described polyol mixture with a trichlorofluoromethane blowing agent.

[0007] U.S. Pat. No. 4,720,571 to Trowell discloses a method of preparing a polyol with improved compatibility with CFC blowing agents by first reacting a mixture comprised of scrap polyethylene terephthalate, dimethyl terephthalate process residue and at least two glycols having a molecular weight higher than that of ethylene glycol, in the presence of an esterification/transesterification catalyst, and subsequently removing glycols from the reaction product.

[0008] U.S. Pat. No. 5,605,940 to Skowronski et al. discloses a polyol utilized in the creation of rigid polyurethane foams and polyisocyanurate foams having superior shrink resistance, strength, and long-term insulating ability. The disclosed polyol is, or contains, a hydroxy terminated polyester having an equivalent weight greater than about 350. The disclosed polyol is reacted with isocyanate with or without an additional glycol component. The preferred reactant stream for production of the described polyol contains phthalic acid or ester residues which may be derived from the production of dimethyl terephthalate, scrap polyalkylene terephthalates, phthalic anhydride, residues from the manufacture of phthalic acid, terephthalic acid, and residues from the manufacture of terephthalic acid, isophthalic acid and trimellitic anhydride. The described polyol utilizes hydrogen containing halo-carbon blowing agents such as HCFC's and optionally simple hydrocarbons.

[0009] U.S. Pat. Nos. 4,521,611 and 4,526,908 to Magnus describe a polyol composition having phthalic anhydride and a dihydroxy alkylene having two to six carbon atoms; propane diols having the middle carbon substituted with methane components, methanol components, hydroxy components, or hydrogen; or radicals of the formula HO—(R³O)_(n)—R³—OH, where R³ is an alkylene radical containing two or three carbon atoms and n is an integer from one through three. The foam making process using the disclosed polyol is carried out with excess polyol and limited isocyanate. The disclosed polyols increase the solubility of flourocarbon blowing agents within the polyol-isocyanate mixture.

[0010] U.S. Pat. No. 4,897,429 to Trowell et al. discloses a polyol blend having tall oil fatty acids, dimethyl terephthalate process residue, and polyhydric alcohol components. The components are reacted in the presence of a transesterification catalyst and then reacted with alkylene carbonates or alkylene oxide. The disclosed improved polyol has increased compatibility with chlorofluorocarbon blowing agents. Trowell ‘602 also discloses an improved polyol blend having tall oil fatty acids.

[0011] U.S. Pat. No. 5,470,501 to Fishback et al. discloses a n agent which increases the solubility of lightweight hydrocarbons within a polyol mixture. The disclosed agent is an aromatic compound having a first substitution of OH, NH₂, COOH, or oxyalkylated addition products thereof, and a second substitution component of C₆—C₂₄ aliphatic, branched or unbranched, hydrocarbon group . The disclosed agent may be unreacted or reacted with the polyol.

[0012] There is a need for an inexpensive and readily available polyol composition containing compatibilizing agents for use with lightweight hydrocarbon blowing agents. There is a further need for a polyol component which increases the emulsification of hydrocarbon blowing agents within the polyol mixture while lowering the overall viscosity of the polyol emulsion allowing for improved flowability during the foam reaction process. There is a further need for a polyol component allowing for emulsification of hydrocarbon blowing agents which maintains the hydrocarbon emulsion for extended periods of time and allows for such hydrocarbon polyol mixtures to be stored. There is a further need to accomplish the foregoing requirements, without detracting from the overall aromatic content of the resulting polymer. There is a further need to accomplish the foregoing requirements without detracting from the flammability of the resulting polymer. There is a further need to accomplish the foregoing requirements while improving the insulating value (R-value=1/k-factor) of the resulting foam. An invented compound allowing for greater emulsification of hydrocarbon blowing agents within foam making ingredients is further desired in order to reduce the use of ozone depleting CFC's and HCFC's in the traditional foam making processes.

SUMMARY OF THE INVENTION

[0013] The improved emulsification of hydrocarbon blowing agents within a polyol mixture, the decreased viscosity of the polyol-blowing agent emulsion, the stabilization of hydrocarbon blowing agent-polyol emulsion, the decrease in flammability, and the improvement in insulating value (R-value) have all been achieved by the invented incorporation of benzoate, substituted benzoate, napthenate or substituted napthalenic glycol adduct in the production of polyurethane and polyisocyanurate foams. The glycol adduct additives yield isocyanate-reactive polyols with improved hydrocarbon blowing agent emulsion stability, and the foams produced therefrom have lower thermal conductivity and lower flammability than those prepared from polyols without the invented additives. The polyester polyol of the invention incorporates the glycol adduct of the named materials as a physical mixture or as a co-reactant with a hydroxy terminated polyester.

[0014] The invented additive can be produced by esterification reaction of the carboxylic acid, or by the transesterification reaction of the corresponding ester or anhydride, with the glycol. The additive can be conveniently produced by mixing the carboxylic acid, or carboxylic acid derivative (ester or anhydride), with the glycol, reacting the mixture at elevated temperature with agitation, and removing the water and/or alcohol so produced. The molecular weight, free glycol content, acidity, hydroxyl number, and viscosity of the polyester product can be controlled as desired by the molar ratio of the acids (or esters, anhydrides and mixtures thereof) to the glycol or glycol mixture. Reaction stoichiometry can be chosen to provide substantially monoadduct or diadduct product, or any monoadduct to diadduct ratio as desired. Generally, an esterification catalyst is added to the reaction mixture to promote the reaction in a suitable time. Any conventional esterification catalyst or mixtures thereof may be used, such as organo tin catalysts, or a metal catalyst, such as tetraisopropyltitanate.

[0015] The invented additive may be produced from substantially pure reactant materials, or in combination with side-stream byproducts from the manufacture of phthalic acid, terephthalic acid, dimethylterephthalate, polyethylene terephthalate, isophthalic acid, dimethylisophthalate, napthalene dicarboxylic acid, or dimethylnapthalenedicarboxylate. The glycol reactant may also be substantially pure, or as mixed or side-streams derived from the manufacture or purification of ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycols, or benzyl alcohol, benzene dimethanol, napthol, butanediol, pentanediol or hexanediol. Similarly, higher functionality triols and tetrols may be incorporated individually or as mixtures with the above glycols, as desired.

[0016] The polyurethane/polyisocyanurate foam produced with the invented additive and blown with simple hydrocarbon blowing agents produce a foam of superior quality to that known in the prior art. The increased emulsification of the hydrocarbon blowing agent due to the invented polyol additive results in an increase in fine, uniform foam cells which produces a foam having an improved insulating value (lower k-value) and lower flammability. The favorable polyol viscosity lowering characteristics of the invented additive result in a polyol emulsion mixture which is easy to manipulate in conventional foam manufacturing equipment. The invented additive also increases the amount of time that a hydrocarbon blowing agent will remain in a stable, unagitated emulsion a polyol.

DETAILED DESCRIPTION

[0017] The polyisocyanurate foam produced in accordance with this invention utilizes benzoic acid, toluic acid, and napthoic acid glycol adducts as compatibilizing agents. As used herein, compatibilizing agents are components which increase the miscibility of a blowing agent within a polyol mixture. More particularly, the described compatibilizing agents increase the polyol miscibility of hydrocarbon blowing agents. As used herein, all descriptions or examples illustrating the use of a benzoic acid glycol adduct also encompass toluic acid glycol adducts, napthoic acid glycol adducts, and other chemically similar glycol adducts.

[0018] Although similar polyol and foam properties may be produced by physical blends of the invented additive with conventional polyester polyols, the invented additive is preferably produced concurrently in the reactor, during the transesterification of dimethyterephthalate residue to produce complex mixtures of the polyester polyols.

[0019] The carboxylic acid components and glycol components of the invented adduct additive interact with the hydroxy terminated polyester (polyol) in several ways. A carboxylic acid may bond to a free glycol to form a mono-adduct, two carboxylic acids may bond to a single free glycol to form a di-adduct, or a carboxylic acid may bond to a glycol bound to the polyester polyol to form an end group on the polyol.

[0020] Particularly suitable components of the invention are aromatic polyesters derived from the reaction of benzoic acid or benzoic acid esters with a free glycol or glycol bound to a polyester polyol:

C6H5—COOH+HO—R′—OH→C6H5COOR′—OH monoadduct

2 C6H5—COOH+HO—R′—OH→C6H5COO—R′—OOCC6H5 diadduct

HOCH2CH2OOC(C6H4)COOCH2CH2OOC(C6H5) endgroup on polyester polyol

[0021] A preferred embodiment is to react the hydroxyl end groups of a hydroxyl-terminated aromatic polyester polyol with the benzoic acid, forming benzoate end groups.

[0022] Another preferred embodiment is to react methyl p-toluate with the glycol endgroups of the polyester polyol, most particularly a polyester polyol produced from phthalic anhydride and diethylene glycol.

[0023] A preferred carboxylic acid component for use in the invented additive is the methyl ester of p-toluic acid, methyl p-toluate or MpT:

[0024] Another preferred carboxylic acid component is napthalene carboxylic acid.

[0025] Preferred glycol components for use in the invented additive are diethylene glycol, polyethylene glycol, 2-methyl-1,3-propanediol, and 2-naphthol.

[0026] The polyurethane/polyisocyanurate foams of the invention are prepared by reacting a polyisocyanate (‘A-side’ component) with a polyol or polyol mixture, blowing agent, and optional catalyst and/or surfactant (collectively, the ‘B-side’ component), such that the ratio of isocyanate equivalents to total polyol equivalents is from about 1.1 to 4.5, wherein the polyol mixture of the invention comprises from about 5% to about 100% of the B-side component.

[0027] The polyisocyanate component employed in the foam forming process can be any of the polyisocyanates known to be useful in the art of polymer formation. Typical polyisocyanates include m-phenylene diisocyanate; p-phenylene diisocyanate; polymethylene polyphenylisocyanate; 2,4-toluene diisocyanate; 2,6-tolylene diisocyanate; dianisidine diisocyanate; naphthalene 1,4 diisocyanate; diphenylene-4,4′-diisocyanate; aliphatic-aromatic diisocyanates, such as xylylene-1,4-diisocyante; xylylene-1,2-diisocyante; xylylene-1,3-diisocyanate; bis(4-isocyanatophenyl) methane; bis(3-methyl-4-isocyanatophenyl) methane; and 4,4′-diphenylpropane diisocyante. A particularly preferred polyisocyanate is the polymeric methyl diphenyl isocyanate (MDI) with a functionality of about 2.7 and a viscosity of about 700 centipoise.

[0028] Any suitable foam blowing agent may be used in preparation of the foams. Preferred foam blowing agents are cyclopentane, isopentane, n-pentane, 2-chloropropane, 1,1,1,2-tetrafluoroethane (HFC-134a); 1,1,1,3,3-pentafluoropropane (HFC-245fa); and n-propylbromide, or mixtures thereof. From 0.3 to 5% water, which generates CO₂ from the reaction between water and the isocyanate, may be used as a coblowing agent.

[0029] The foam forming mixture contains the invented adduct or mixture of adducts, a polyester or polyether copolyol, a catalyst that will promote the urethane or isocyanurate reaction as desired, a surfactant such as the various silicone or organic surfactants available to the rigid foam industry, the foam blowing agent, and, optionally a phosphorus or halogen-containing flame retardant, water, and other additives or fillers as needed for the particular formulation and end use. The above mixture, commonly referred to as the ‘B-side’ component, is brought together with the polymeric isocyanate or ‘A-side’ component under conditions of controlled temperature, pressure, and component flow, and intimately mixed by high-pressure impingement. The resulting reacting mixture is then deposited on facing materials or poured into suitable molds for fabrication of the desired finished product.

TEST METHODS

[0030] In the following examples, the hydroxyl number was measured in the various components using the ASTM D 4274 standardized testing method. The percent NCO was determined using the ASTM D 1786 standardized testing method. Viscosity was determined by the Brookfield test. The NCO/OH index was determined by calculation. Foam density was determined by ASTM C 303. Thermal conductivity (k-factor) was determined by ASTM C 236, and flammability (the hot plate test) was determined by ASTM D 1692.

[0031] As used herein, cream time refers to the time required for foaming to commence in a fully mixed system of the polyol mixture and isocyanate, using the starting materials at 250° C. Tack free time is the time required from initial mixing for the foam to achieve a condition such that an exposed surface thereof is tack free when contacted lightly by a dowel or the like. Gel time is the time at which the foam gives strings of polymer when tested with a dowel or the like. Rise time is the time for the foam to complete foaming.

EXAMPLES Example 1

[0032] Conventional Polyester Polyol Synthesis

[0033] Example 1 illustrates the preparation of conventional polyester polyols. Weights of the reaction components are shown in Table 1. The components are charged to a reaction flask fitted with a mechanical stirrer, Vigreaux column, reflux condenser, reflux receiver, thermometer well, thermometer and temperature controller, and a nitrogen blanket. Reactor contents were gradually heated to 235° C. while the distillate was collected and weighed. The reaction was terminated after 2-4 hours, when the overhead condenser temperature dropped to <50° C. and the product acid number was less than 1.5. “B side stability” is the stability of the mixture of polyol and blowing agent, with any applicable catalysts, surfactants, or other traditional additives. TABLE 1 Component, grams Phthalic Anhydride 272 0 0 DMT (dimethyl terephthalate) 0 275 0 DMT Residue 0 0 275 Diethylene Glycol 224 224 232 Tyzor TPT (catalyst) 1.9 1.7 1.7 Distillate, grams 78 Hydroxyl Number 232 236 251 Viscosity (cp) 7800 8300 9450 Acid number 1.3 0.9 1.5 Polyol Stability stable crystallize stable B side stability emulsion emulsion emulsion Emulsion stability (1 Hr) yes yes no Emulsion Stability (24 Hr) no no no

Example 2

[0034] Conventional Foam Forming Formulation

[0035] Example 2 illustrates a conventional foam forming procedure using a hydrocarbon blowing agent, here pentane. Ingredients shown in Table 2 are charged to a suitable container, in the order shown. The pentane mixture is added last, mixed, and adjusted to constant weight. The premixed ‘B-side’ is then placed in a water bath and adjusted to 25° C. Polymeric isocyanate, also at 25° C., is then added and the total is mixed at 5000 rpm for 8 seconds. After mixing, the material is poured into a suitable mold, and the reactivity times are recorded. Foam is allowed to cure for 24-48 hours, and then cut for physical property testing. TABLE 2 Polyol Hydroxyl Number 240 parts by weight Terate 2541 100 TCPP 15 K-octoate (catalyst) 4.2 Polycat-5 0.15 Silicone Surfactant 2.5 Water 0.5 Pentane 23 NCO/OH index 3.00 Isocyanate 209 Foam reactivity: Cream, secs. 10 Gel, secs. 21 Tackfree, secs. 28 Rise time, secs. 61 Foam density 1.85

Example 3

[0036] Synthesis of Polyols of the Invention

[0037] Table 3 shows the physical properties for polyols produced by the procedure shown in Example 1, using conventional polyester polyol synthesis. TABLE 3 Polyol Designation 8256-56-2 8256-82 8256-86 8256-68 Parts by weight: DMT Residue 1160 836 711 873 Methyl benzoate 690 0 0 0 Methyl p-toluate 0 182 213 0 2-napthol 0 0 0 198 Diethylene glycol 1773 800 955 654 Tetraisopropyltitanate 1.8 1.2 0.7 0.8 Total 3624.8 1819.2 1879.7 1725.8 Reaction Temperature, 230 230 225 225 C. Reaction Time, hours 4.00 3.75 4.75 6.00 Distillate, grams 479 230 95 271 Hydroxyl number, 237 258 251 248 mg.KOH/gr. Viscosity, cps 3600 2600 4500 17,500 Acid number, mg.KOH/ 0.9 0.3 0.3 0.6 gr. Emulsion stability Yes Yes Yes Yes (24 Hr) Foam designation in C D E F Example 4

[0038] The physical properties of the polyols produced in accordance with this invention, show improved polyol stability over those polyols produced by traditional methods shown in Example 1. The foams produced in Example 4, utilizing the polyols of this example demonstrate dramatically improved properties over comparable foams which do not incorporate polyols produced in accordance with the present invention.

Example 4

[0039] Table 4 shows the laboratory synthesis and physical properties of foam produced using the polyols of the invention (C,D,E, and F prepared in example 3). TABLE 4 Foam Designation A B C D E F Polyol Terate 2541 Stepanol 2352 8252-56-2 8256-82 8256-86 8256-68 Polyol Hydroxyl Number 240 245 237 258 251 248 parts by weight: Polyol 92.5 85 92.5 92.5 92.5 92.5 TCPP (Tris 2chloropropylphosphate) 15 15 15 15 15 15 flame retardant Potasium Octoate (catalyst) 4.2 3 4.2 4.2 3.5 4.2 PMDETA (pentamethyldiethylene triamine) foam catalyst 0.13 0.12 0.12 0.12 0.14 0.12 Silicone Surfactant 2.5 2.5 2.5 2.5 2.5 2.5 Water 0.5 0.5 0.5 0.5 0.5 0.5 Pentane 23.3 20.6 22.3 23.6 23.8 20.1 (70% cyclopentane/30% isopentane) NCO/OH index 3.00 3.00 3.00 3.00 3.00 3.00 Isocyanate 196 182.9 207 223 213 223 B-side viscosity, cps. 1200 1500 1200 1100 1500 2200 Emulsion stability, 24 hrs. yes yes yes yes yes yes Foam reactivity: Cream, secs. 12 16 11 11 11 9 Gel, secs 31 35 21 25 24 23 Tack free, secs. 41 62 26 30 33 32 Rise time, secs 63 102 53 71 68 65 Foam density, lbs/ft³ 1.86 1.93 1.91 1.91 1.95 2.11 Thermal conductivity: k-factor, initial 0.144 0.142 0.128 0.145 0.139 0.135 k-factor, aged 90 days 0.162 0.161 0.149 0.156 0.154 0.153 Flammability, hotplate test % Dimensional change −12 −17 +4.2 +4 4 1.1 % weight loss 17 18 18 18 17.5 19 % thickness loss 14 23 6 6 15 9

[0040] As shown above, the ployols produced in accordance with this invention (samples C,D,E, and F) produced a blown foam having superior qualities than comparable foams produced from standard polyols. Foams produced according to the present invention exhibited improved initial and aged k-factors, as well as improved flammability characteristics.

Example 5

[0041] Flowability Measurements in foams

[0042] Table 5 illustrates the improved flowability of polyols of the invention (foam formulations C and D in Example 3), compared to a conventional control polyol, in foams prepared in the laboratory. Flowability is measured with an ultrasonic rate-of-rise detector (Fomat®, produced by Messtechnik GmbH, of Germany). Flowability is determined by measuring the foam rise height at gelation of the polymer, and dividing this by the total rise height of the foam. A higher percentage of rise height at gelation indicates improved flowability of the liquid chemicals prior to polymerization. TABLE 5 Foam Designation Control C D Polyol S-2412 8256-56-2 8256-82 parts by weight Polyol 100 100 100 Flame retardant 0 2.5 2.5 K-Octoate 3.2 2.8 2.8 PMDETA 0.04 0.04 0.04 Surfactant 2.5 2.5 2.5 Water 0.5 5 0.5 Pentane 22.2 21.5 21.3 Total 128.44 134.34 129.64 Index 3.00 3.00 3.00 Polymeric MDI 207 203 200 % rise height at gel 78.0 88.4 81.8

Example 6

[0043] Commercial Scale Laminator Trial with Polyol of the Invention

[0044] Table 6 shows the results of a polyol of the invention, run on a commercial scale laminate foam process. The commercial laminator measures the foam flowability by use of a ‘wet’ and a % packing factor. The yield density is obtained by dividing the total pounds of foam chemical, as determined by a mass flow meter, into the total cubic feet of laminate board produced. The packing factor is the percentage difference between the foam core density and the ‘wet’ density. Lower packing factors demonstrate better flow in the foam lamination process. TABLE 6 8256-56-2 (polyol w/methyl Commercial benzoate additive) phthalate polyol Target linespeed 95 96 Actual linespeed 97 98 Board density 1.77 1.75 Core density 1.73 1.65 Wet density 1.81 1.81 Yield, % pack (packing factor) 4.6 9.7

Example 7

[0045] Laboratory Foams demonstrating use of 2-chloropropane blowing agent with polyols of the Invention

[0046] Table 7 demonstrates the improvement in initial and aged k-factor, flammability and rise height at gelation, for foams produced with polyols of the invention, using 2-chloropropane as the blowing agent. Once again, higher values of rise height at gelation are favorable, while lower values of k-factor and flammability are favorable. TABLE 7 Control C D Foam designation Stepanol 2352 8256-56-2 8256-82 parts by weight Polyol 90.00 90.00 90.00 Flame retardant 10.00 10.00 10.00 K-Octoate 3.20 2.80 2.80 PMDETA 0.04 0.04 0.04 Surfactant 2.50 2.50 2.50 Water 0.50 0.50 0.50 2-chlorpropane 21.80 21.50 21.30 Total 128.04 127.34 127.14 Index 3.00 3.00 3.00 Polymeric MDI 207.00 203.00 200.00 % rise height at 80.0 86.7 87.4 foam gelation Thermal conductivity: k-factor, initial 0.137 0.136 0.135 k-factor, aged 30 days 0.153 0.143 0.143 Flammability, hotplate test % Dimensional change −6.70 −0.40 +7.2 % weight loss 13.80 13.00 13.60 % thickness loss 14.00 5.90 0.50 foam gelation

Example 8

[0047] Use of the Polyester of the Invention as an Additive in the Foaming Process, to improve Flowability

[0048] Table 8 demonstrates the use of a polyol prepared in accordance with the invention, as a diadduct to dipropyleneglycol, used as an additive in the foaming process. Data indicates that use of the additive provided better flow in the foaming process as evidenced by lower free-rise and board densities. TABLE 8 parts by weight Terate polyol 90 90 Nonbenzoate flow additive 10 0 Benzoate flow additive 0 10 Silicone surfactant 1.5 1.5 Potassium Octoate catalyst 3.7 3.7 Polycat 41 catalyst 0.3 0.3 Polycat 5 catalyst 0.15 0.15 AB-80 flame retardant 15 15 Water 0.1 0.1 Cyclopentane 17.57 17.57 Isopentane 7.53 7.53 Polymeric isocyanate 183 183 Free rise Density 1.87 1.75 % free rise density improvement Control 6.86% Board density 2.09 2.00 % board density improvement Control 4.50%

[0049] It will therefore be readily understood by those persons skilled in the art that the present invention is susceptible of broad utility and application. Many embodiments and adaptations of the present invention other than those herein described, as well as many variations, modifications and equivalent arrangements, will be apparent from or reasonably suggested by the present invention and the foregoing description thereof, without departing from the substance or scope of the present invention. Accordingly, while the present invention has been described herein in detail in relation to its preferred embodiment, it is to be understood that this disclosure is only illustrative and exemplary of the present invention and is made merely for purposes of providing a full and enabling disclosure of the invention. The foregoing disclosure is not intended or to be construed to limit the present invention or otherwise to exclude any such other embodiments, adaptations, variations, modifications and equivalent arrangements, the present invention being limited only by the claims appended hereto and the equivalents thereof. 

We claim:
 1. A polyisocyanate reactive, hydrocarbon blowing agent compatible, polyol solution comprising: at least one polyester polyol; a compatibilizing additive or mixture of additives selected from the group including: a benzoate glycol adduct, a substituted benzoate glycol adduct, a napthenate glycol adduct, a substituted naphthenate glycol adduct; a toluate glycol adduct, and a substituted toluate glycol adduct; and, at least one hydrocarbon blowing agent.
 2. The polyol solution of claim 1, wherein the compatibilizing additive is reacted with the polyol.
 3. The polyol solution of claim 1, wherein the compatibilizing additive and polyol are unreacted.
 4. The polyol solution of claim 1, further comprising: a flame retardant additive.
 5. The polyol solution of claim 1, further comprising: a surfactant.
 6. The polyol solution of claim 1, wherein said hydrocarbon blowing agent is selected from the group comprising: cyclopentane, isopentane, n-pentane, 2-chloropropane, 1,1,1,2-tetrafluoroethane (HFC- 134a), 1,1,1,3,3 -pentafluoropropane (HFC-245fa), and n-propylbromide, or mixtures thereof.
 7. The polyol solution of claim 1, wherein said glycol component of said adduct is selected from the group comprising: diethylene glycol, polyethylene glycol, 2-naphthol, and 2-methyl-1,3-propanediol.
 8. The polyol solution of claim 1, wherein the additive is selected from the group comprising: methyl p-toluate glycol adduct and napthalene carboxylic acid glycol adduct.
 9. A polyisocyanate based foam comprising the reaction product of at least one polyester polyol; a compatibilizing additive or mixture of additives selected from the group including: a benzoate glycol adduct, a substituted benzoate glycol adduct, a napthenate glycol adduct, a substituted naphthenate glycol adduct, a toluate glycol adduct, and a substituted toluate glycol adduct; and, at least one hydrocarbon blowing agent.
 10. The polyisocyanate based foam of claim 9, wherein the compatibilizing additive is reacted with the polyol.
 11. The polyisocyanate based foam of claim 9, wherein the compatibilizing additive and polyol are unreacted.
 12. The polyisocyanate based foam of claim 9, wherein the reaction product further comprises: a flame retardant additive.
 13. The polyisocyanate based foam of claim 9, wherein the reaction product further comprises: a surfactant.
 14. The polyisocyanate based foam of claim 9, wherein the blowing agent is selected from the group comprising: cyclopentane, isopentane, n-pentane, 2-chloropropane, 1,1,1,2-tetrafluoroethane (HFC- 134a), 1,1,1,3,3 -pentafluoropropane (HFC-245fa), and n-propylbromide, or mixtures thereof.
 15. The polyisocyanate based foam of claim 9, wherein the glycol component is selected from the group comprising: diethylene glycol, polyethylene glycol, 2-naphthol, and MP diol ®.
 16. The polyisocyanate based foam of claim 9, wherein the additive is selected from the group comprising: methyl p-toluate glycol adduct and napthalene carboxylic acid glycol adduct. 